Fuente: Foods - Revista científica (MDPI) Foods, Vol. 15, Pages 464: A Konjac Glucomannan-Based Antibacterial Packaging Film with Humidity-Triggered Release of Cinnamaldehyde
Foods doi: 10.3390/foods15030464
Authors:
Yibin Chen
Hao Liu
Kaijun Sun
Qibiao Weng
Ying Yan
Liping Xiao
Ziwei Ye
Chengrong Wen
Jie Pang
Qian Ning

To meet the challenge of microbial contamination of food, smart packaging materials with active controlled-release functions have become a research hotspot. In this study, a humidity-responsive antimicrobial composite film was constructed by introducing cinnamaldehyde@β-cyclodextrin inclusion complexes (CIN@β-CD ICs) into a konjac glucomannan/polyvinyl alcohol/lithium chloride (KGM/PVA/LiCl) matrix. Characterization results showed that the CIN@β-CD ICs formed a dense structure through hydrogen bonding, which enhanced the thermal stability, mechanical strength (tensile strength: 20.83 MPa) and surface hydrophilicity (water contact angle < 60°) of the film. The film acted as a humidity-triggered release system for CIN, enabling controlled antimicrobial delivery: at high humidity (98% RH), the film rapidly swelled and accelerated the release of CIN, with a cumulative release rate of 87.29% over 7 days, whereas the release slowed significantly at low humidity (43% RH). The antimicrobial activity of the released CIN was strongly influenced by ambient humidity, with the effect enhanced under high humidity conditions. It is noteworthy that the film containing 0.2% ICs exhibited the optimal antimicrobial performance among the formulations studied. This study elucidates a mechanism for humidity-triggered release through multicomponent synergism, which provides a feasible strategy for the design of environmentally friendly, smart packaging materials with high antimicrobial activity.